As it is well known, in a smart entry system for a vehicle, a door of the vehicle is locked and unlocked by automatically detecting whether a user carrying an electronic key specific to the vehicle is approaching or coming away from the vehicle through wireless communication with the electronic key.
In such a smart entry system, if the door is fully automatically locked and unlocked regardless of a user's intention, problems may occur such as degradation in usability and an increase in time elapsed from when the user exits the vehicle to when the door is locked. As a result, the user may be anxious about whether the door is actually locked.
In a smart entry system disclosed in Japanese Patent No. 3582384, a user can manually input a door lock command through a lock switch (SW) provided on the exterior (e.g., near a door handle) of a vehicle in order to lock a door of the vehicle. A door of the vehicle is locked in response to an operation of the lock switch, if a door lock condition is met. The door lock condition is that an electronic key specific to the vehicle is located outside the vehicle and is not located inside the vehicle.
For example, a vehicle-interior/trunk-interior key check is performed to check whether the electronic key is not located inside the vehicle, and a vehicle-outside key check is performed to check whether the key is located outside the vehicle.
Such a key check procedure to determine whether the door lock condition is met is performed to prevent the door from being locked with the electronic key left inside the vehicle. As shown in FIG. 5, the key check procedure starts after the lock SW is pressed down.
Therefore, it takes much time to verify the door is locked after pressing down the lock SW.